Touch screen interface for laser processing

ABSTRACT

A touch screen user interface for an optical device wherein the touch screen user interface is connected to a controller which controls motion stages permitting the motion stages to re-position, re-size, re-orient or focus the field of view of the optical device in response to commands input from the touch screen user interface.

TECHNICAL FIELD

This invention is a touch screen user interface for imaging devices. Inparticular it is a touch screen interface for microscopy systems,wherein the microscope has motion stages for holding the specimen to beexamined and where the touch screen user interface is connected to acontroller which receives commands from the touch screen user interfaceand converts them into commands which drive the motion stages. In moreparticular it is a touch screen user interface for optical microscopywherein the user can enter commands to the system via touch screen userinterface and have the motion stages respond to those commands as if theuser had moved the specimen directly rather than touching an image ofthe specimen on a touch screen.

BACKGROUND OF THE INVENTION

The field of optical microscopy is broad, encompassing many types ofoptical and other devices which rely upon magnification to image orexamine or extract information regarding specimens that are smaller thanare normally visible with the un-aided human eye. In particular we areconcerned with computer-assisted microscopes, wherein a computer isattached to the microscope to provide a display of the image data beingproduced by the microscope and a user interface to control the variouscapabilities of the microscope. In addition to optical microscopes, suchdevices as electron microscopes or confocal microscopes also havecomputers for image acquisition, display, management and user interfacefunctions. In more particular we are concerned with optical microscopesused in laser processing systems, where the microscope is used to alignand plan the laser beam path with respect to the specimen and optionallyinspect the results of laser processing. Exemplary laser processingsystems that use optical microscopes in this fashion include laserablation inductively coupled plasma mass spectroscopy (LA ICP-MS), laserablation inductively coupled plasma emission spectroscopy(ICP-OES/ICP-AES) and matrix assisted laser desorption ionization timeof flight (MALDI-TOF) spectroscopy.

A problem that computer assisted microscopy systems have in common isthat the user needs to select the point on the specimen at which thelaser impinges. This is to control the composition and quality of thesample of the specimen created by the laser. Often the specimen issealed in a sample chamber with limited access. This means that thefield of view must often be moved around relative to the specimen underexamination using remote controls. Added to this is the 3-dimensionalnature of some specimens and the limited depth of field of typicalmicroscope systems at high magnifications which combine to require thatthe field of view be moved in three dimensions including possibly threedegrees of rotation in order to image a specimen as desired. A problemis that the controls to change the field of view in this fashion may bedivided between two or more motion elements and coordinating thesemotions to provide a desired transition of the relationship betweenfield of view and specimen can be a difficult task. In any case,altering the relation between the laser beam and the specimen is acommon task in these types of systems. Any improvement in user interfacethat decreased setup time and made positioning specimens easier andfaster would be of positive benefit.

U.S. Pat. No. 5,859,700 HIGH RESOLUTION IMAGING MICROSCOPE (HIRIM) ANDUSES THEREOF, inventor Mary M. Yang, Jan. 12, 1999, describes a type ofdigital imaging microscope, specifically a digital imagingspectrophotometer and the computer interfaced to this microscope indetail. Described in particular is the ability of the computer toacquire large volumes of spectroscopic data and make it available fordisplay. U.S. Pat. No. 6,991,374, COMPUTER CONTROLLED MICROSCOPE,inventors Nicholas James Salmon and Ernst Hans Karl Stelzer, Jun. 31,2006, describes a computer controlled optical microscope that canremember the parameter settings from on set of image data and apply itto related image data sets as they are recorded by the system. U.S. Pat.No. 7,647,085, METHOD AND APPARATUS FOR INVESTIGATING TISSUE HISTOLOGY,inventors Michael Roger Cane, Michael Andrew Beadman and Symon D'OylyCotton, Jun. 12, 2010, describes a computer-assisted optical microscopewith a touch screen interface, but the touch screen is only used tocommence operational or programming steps.

Touch screen technology is well-known and widely commercially available.It involves adding equipment to a display to allow the user to inputcommands to the system by touching a display screen. Touch screendisplays typically work either by detecting changes in capacitancecaused by the user's touch or by detecting changes in infraredtransmission across the screen. In response to a user's touch, thescreen transmits the coordinates of the point on the screen touched to acontroller. The controller typically interprets the coordinates of thescreen touch as being from a pointing device such as a mouse ortrackball and takes appropriate actions depending upon how it has beenprogrammed.

What is needed then is a touch screen user interface forcomputer-assisted microscopy systems that is operatively connected tomotion stages to permit the user to input commands to the motion stagesto alter the field of view of the system and improve system setup,increase throughput and overcome the problems associated with achievingdesired changes in the relationship between the specimen and the laserbeam.

SUMMARY OF THE INVENTION

This invention is a touch screen interface integrated with an opticalmicroscope in a laser processing system. Aspects of this inventioninclude an optical system having a controller, a field of view and aspecimen to be viewed, and includes a touch screen user interfaceoperatively connected to the controller. Other aspects of this inventioninclude motion stages operatively connected to the controller which holdthe specimen and change the relationship between said specimen and saidfield of view. The controller is operative to input user commands from atouch screen user interface, transform the user commands into outputcommands and output the output commands to the motion stages. The motionstages, in response to said output commands, alter the relationshipbetween said field of view and the specimen according to input usercommands from a touch screen.

Exemplary laser processing systems that could benefit from thisinvention include laser ablation inductively coupled plasma massspectroscopy, laser ablation inductively coupled plasma emissionspectroscopy and matrix assisted laser desorption ionization time offlight spectroscopy. A schematic diagram of an embodiment of thisinvention is shown in FIG. 1. These systems can all employ opticalmicroscopes to view the specimen to be processed. In operation aspecimen is placed in the system and the optical microscope is used toselect a start position for the laser beam to impinge upon the specimenand begin processing. This is accomplished by acquiring images of afield of view of the specimen and displaying it on a touch screenmonitor. This display is “live” and continuous, meaning that any changesin the field of view of the camera will be displayed on the touch screenmonitor. An example of this touch screen display is shown in FIG. 2 a.On the monitor, a graphic overlay indicates the position at which thelaser beam will initially impinge upon the specimen. The monitor mayalso display a graphic overlay showing the tool path along which thelaser beam will be subsequently directed to impinge the specimen. Toalter the position at which the laser beam will impinge the specimen,the user touches the screen and drags a finger across the screen. Thecontroller detects the motion of the user's finger on the screen andthen directs the motion stages to move the specimen with respect to thefield of view of the camera in order to make the image of the specimenon the touch screen appear as if the user had moved the image itself,rather than repositioning the sample in the field of view.

FIGS. 2 a and 2 b illustrate how the invention is used to select a newstart point for laser processing. Assuming that the user desires tochange the start point for laser processing in FIG. 2 a, the user beginsby touching the screen anywhere on the image of the specimen. When theuser drags a finger on the screen, the touch screen interface detectsthe movement of the user's finger on the screen and directs the motionstages to physically move the specimen under the field of view of theoptical microscope, thereby changing the image being viewed on themonitor. By appropriate programming of the controller, touching thescreen and dragging a finger across the screen will make the image dataon the screen appear as if it were being dragged by the finger. Inactuality the controller is directing the motion stages to move thespecimen in the field of view of the camera to simulate the motion thatwould occur if the user had moved the specimen by hand rather thandragging a finger across a touch screen. FIG. 2 b shows the touch screenfollowing user input showing the movement of the image data in relationto the onscreen graphic overlay showing the laser beam impact point.

The controller can be programmed to offer many different options forresponding to user touch screen input. The controller can move themotion stages to cause the image data to move either more or less thanthe motion input from the screen. This would have the effect of eitheraccelerating specimen motion or making it more sensitive to small motionfor fine adjustments. The controller can also interpret some motionsrelating to Z-axis motion, where moving a finger up and down on thescreen, for example, would move the specimen up and down in the field ofview, potentially moving the specimen in and out of focus. Other motionscan be programmed to move the specimen in 3D, if desired. Alternatively,the controller can be programmed to move the cursor or other screengraphics in response to user touch screen input. For example, in thismode, the user could move the point where the laser beam will impingeupon the specimen by touching the screen and moving the graphic devicewhich indicates the location of the laser beam. The controller thendirects the motion stages to move the specimen in relation to the laserbeam in order to have it impinge at the selected position.

Adding a touch screen interface, controller and motion stages to anoptical microscope equipped laser processing system allows the user tointeract with a touch screen and have it appear as if they were directlymanipulating a specimen. This is significant for two reasons. The firstis that the specimen may be sealed in a specific environment forprocessing. Laser processing systems sometimes require the specimen tobe sealed in an inert gas atmosphere, such as nitrogen or argon, toallow processing, making the specimen difficult to manipulate directly.In addition, in cases where complex motion stages are used to move thepart, motion of two or more actuator/stage/encoder units may have to becoordinated to effect a desired change in position. Adding anappropriately programmed touch screen interface reduces all of thesemotions to a simple screen touch. Providing a laser processing systemwith the improvements described herein will make the system easier tooperate and increase system throughput.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1. Diagram of touch screen laser processing system

FIG. 2 a. Diagram showing touch screen with image and graphics

FIG. 2 b. Diagram showing touch screen with image and graphics moved.

FIG. 3. Diagram showing touch screen with image and toolpaths.

FIG. 4. Diagram of touch screen laser processing system with additionalfield of view camera.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

This invention is a touch screen interface integrated with an opticalmicroscope in a laser processing system. An embodiment of this inventionis shown in FIG. 1. This embodiment includes a specimen 10, and a laser12 having a laser beam 14. The laser beam 14 is directed to the specimen10 by an optical microscope 16. This optical microscope 16 is anexemplary optical device which combines the optical axes of the laser 10and the camera field of view 20 to permit the camera 18 to image theportion of specimen 10 that falls within the field of view 20. Otheroptical devices can also be used to combine the laser beam 14 and camerafield of view 20, for example a half-silvered mirror (not shown). Inaddition, the system can be constructed so that the camera field of view20 and the laser beam 14 are not on the same optical axis and thereforerequire separate optical devices (not shown) to direct the laser beam 14and camera field of view 20. In this case the controller 22 calculatesthe actual offset between the camera field of view 20 and the laser beam14 and applies this offset to subsequent calculations.

The camera 18 is connected to a controller 22 which directs the camerato acquire image data and transmit it to the controller 22. Thecontroller 22 displays the image data from the camera 18 on the touchscreen monitor 24. The camera 18 is typically a video type camera whichis capable of acquiring image data continuously or at frame rates highenough to appear continuous. The controller 22 is also connected tomotion stages 26 which move the specimen 10 in relation to the laserbeam 14 and the camera field of view 20. Although this embodiment showsthe specimen 10 being carried by the motion stages 26, the system couldalso move the laser beam 14 and the field of view 20 in relation to thespecimen 10, or split the motion between these elements by attachingmotion stages to each (not shown). Embodiments of this invention canalter the position of the specimen 10 with relation to the laser beam 14and field of view 20 in up to three dimensions (X, Y and Z) and threerotations (rho, phi and theta) about three axes to permit the system toapply the laser beam 14 to any desired portion of the specimen 10.

In an embodiment of this invention the laser beam 14 is used to ablatematerial from the specimen 10 to permit examination of the ablatedmaterial. It is typically the case that the user desires to select aparticular portion or portions of the specimen 10 to ablate forexamination. For example, the specimen 10 may be composed of more thanone type of material and the user desires to study only one of thematerials. The user would use the image of the specimen 10 fallingwithin the field of view 20 displayed on the touch screen 24 to positionthe laser beam 14 on the specimen 10 by touching the touch screen 24 andthereby directing the controller 22 to command the motion stages 26 tomove the specimen 10 with respect to the laser beam 14 and field of view20. This process is illustrated in FIGS. 2 a and 2 b. FIG. 2 a shows anembodiment of this invention with a touch screen display 30 displayingan image of a specimen 32. On the touch screen display 30 overlaid onthe image of the specimen 32 are overlay graphics indicating the point34 at which the laser beam 14 will impinge upon the specimen when thelaser is directed to emit a laser beam. FIG. 2 b shows how the user canalter the point 34 at which the laser beam will impinge upon thespecimen 10. In FIG. 2 b the user touches the screen at 38 and drags thefinger across the screen to 40 along the path indicated by the arrow.This causes the controller 22 to direct the motion stages 26 to move thespecimen 10 within the field of view 20, causing the image of thespecimen 32 to change on the touch screen display 30, thereby moving thepoint 34 at which the laser will impinge the specimen 10.

At this point the user typically directs the laser to emit a beam 14 andablate material. Note that this motion can be programmed to eithertranslate the motion of the user's finger on the screen 38, 40 intoexactly matching the motion of the relation between the specimen 10 andthe camera field of view 20, thereby allowing the user to alter therelationship between the specimen 10 and the camera field of view 20 andhence the location of the displayed image of the specimen 32 on thetouch screen display 30 in a one-to-one correspondence to the motion ofthe user's finger on the screen 38, 40. In other embodiments, the systemis programmed to either magnify or minify the user's input finger motionon the screen 38, 40. In these cases the relationship between thespecimen 10 and the field of view 20 can be programmed to make the imageof the specimen 32 on the touch screen display 30 move more or less thanthe user's input finger motion 38, 40, thereby either exaggerating theinput motion to speed movement over a larger specimen area or reducingthe input motion to improve precision.

Directing the motion stages 26 in response to user input from the touchscreen 30 in this fashion requires that the controller 22 transform theinput user commands such as generated by dragging a finger from point 38to point 40 from screen coordinates to output commands for the motionstages. This may involve splitting the motion between multiple axes ofthe motion stages. For example, if the specimen 10 is held on a pair ofX, Y stages, a diagonal movement input on the screen 30 would have to betransformed by the controller 22 into output commands to both the X andY axes of the motion stages 26 to cause a diagonal movement of thespecimen 10 that corresponds to the diagonal user command input on thetouch screen 30. Another example would be if the specimen had threedimensional surface detail. In this case, movement of the field of viewof the camera on the specimen may cause the optical microscope to go outof focus if the height of the specimen changes even slightly when movingto a new area to be imaged. Output commands would have to be generatedby the controller 22 indicating that the system needs to refocus.Re-focusing could be accomplished by having motion stages move opticalelements in the microscope 16, move the specimen 10 up or down or movethe microscope 16 up or down or some combination of these motions (notshown).

FIG. 3 shows further embodiment of the instant invention, wherein atouch screen display 41, displays an image of a specimen 42. On theimage of the specimen 42 exemplary tool paths 44, 46, 48 are shown whichindicate multiple locations where the laser will be directed to ablatematerial from the specimen. Shown are a raster pattern 44, a collectionof points 46 and an arbitrary path 48. These exemplary tool paths 44,46, 48 are designed by the user and associated with the image of thespecimen using graphics input software (not shown). The differencebetween these tool paths and the points indicated in FIGS. 2 a and b isthat these patterns are associated with locations on the specimen andwhen the user moves the image of the specimen 42 using this touch screen42, the tool paths 44, 46, 48 move along with the image of the specimen,indicating that the laser will ablate materials from the same locationon the specimen regardless of where the specimen is moved in the fieldof view.

Another embodiment of this invention is shown in FIG. 4. This embodimenthas a second camera 50 with a large field of view 52 which is displayedon a second monitor having a touch screen 54. This touch screen monitor54 is in communication with the controller 22 to input commands that aretransformed and result in movement of the motion stage 26. The highresolution camera 18 continues to view a high resolution view of thespecimen 10 through the microscope 16. In this embodiment, the largefield of view camera 50 and touch screen monitor 54 can be used to movethe specimen with relation to the laser processing system while thesmall field of view (high resolution) camera 18 and monitor 24 is usedto view the specimen. In operation, the system may have one or two touchscreen interfaces or combine the displays on one monitor.

Having hereby disclosed the subject matter of the present invention, itshould be obvious that many modifications, substitutions, and variationsof the present invention are possible in view of the teachings. It istherefore understood that the invention may be practiced other than asspecifically described, and should be limited in its breadth and scopeonly by the following claims.

1. A laser processing system having a specimen to be processed,comprising: a controller; a first camera having a first field of viewoperatively connected to said controller; a touch screen user interfaceoperative to input user commands and operatively connected to saidcontroller to display images from said first camera; motion stagesoperatively connected to said controller which change the relationshipbetween said specimen and said first field of view; said controllerbeing operative to accept said input user commands from said touchscreen user interface, transform said user commands into output commandsand communicate said output commands to said motion stages; wherein saidmotion stages, in response to said output commands, alter therelationship between said first field of view and the specimen accordingto said input user commands.
 2. The laser processing system of claim 1wherein said laser processing system is one of laser ablationinductively coupled plasma mass spectroscopy, laser ablation inductivelycoupled plasma emission spectroscopy, or matrix assisted laserdesorption ionization time of flight spectroscopy.
 3. The laserprocessing system of claim 1 wherein said first camera images saidspecimen using an optical microscope.
 4. The laser processing system ofclaim 1 wherein said system has a second camera operatively connected tosaid controller for imaging a second field of view which is larger thanthe first field of view.
 5. A method for controlling an laser processingsystem having a specimen comprising: providing a controller having inputand output commands; providing a first camera having a first field ofview operatively connected to said controller; providing a touch screenuser interface operative to input user commands and operativelyconnected to said controller; providing motion stages operativelyconnected to said controller which change the relationship between saidspecimen and said first field of view; inputting user commands from saidtouch screen user interface and communicating said input user commandsto said controller as said input commands; transforming said inputcommands with said controller into said output commands andcommunicating said output commands to said motion stages; wherein saidmotion stages, in response to said output commands, alter therelationship between said first field of view and the specimen accordingto said input user commands and thereby control said laser processingsystem.
 6. The method of claim 4 wherein said laser processing system isone of laser ablation inductively coupled plasma mass spectroscopy,laser ablation inductively coupled plasma emission spectroscopy, ormatrix assisted laser desorption ionization time of flight spectroscopy.7. The method of claim 1 wherein said first camera images said specimenusing an optical microscope.
 8. The method of claim 1 wherein a secondcamera operatively connected to said controller is provided which imagesa second field of view which is larger than said first field of view.